Synthetic biology – curse or blessing?

When Marie Curie discovered nuclear radiation, she was certainly not aware of the consequences of her invention. From nuclear power plants up to the development of the atomic bomb, destroying Hiroshima – no one could have imagined the extent of radioactivity’s impact. As this example perfectly illustrates, the invention itself is neither good nor bad from the beginning. What counts is the intention of its user.

Exactly this question must be considered when talking about the risks and opportunities of synthetic biology. One must balance ethical questions, dangers of misuse or release of GMOs in the environment with huge chances: genetic therapies, drug synthesis or renewable biofuel production. To make this discussion even more complicated, establishing genetic modification does not only depend on ethical questions or environmental influence, but also on economic factors and political decisions. Therefore, we must keep in mind that the debate on synthetic biology is highly controversial and above all very complex.

This is why we want you to form your own opinion on this topic by providing a brief overview of synthetic biology. The basis of synthetic biology is the ability of changing the universal code of life – the DNA. By modifying the genetic code, organisms can gain completely new functions and characteristics. One of the most famous examples for this gain-of-function modification: Enabling E. coli, common gut bacteria, to produce human insulin. This way, genetic modification has had a major impact on fighting one of the most widespread diseases in our today’s society – diabetes. As you can see, for pharmaceutical industries and subsequently, our well-being, biosynthetic drug production plays a more crucial role year by year. However, synthetic biology does not only offer to transfer specific abilities between different organisms, but it also enables scientists to engineer them. Engineering in terms of genetic modification describes the creation of regulatory circuits. Integrating a whole new metabolism pathway or changing behavior and interaction of an organism with its environment can be achieved by genetic engineering. These circuits consist of different building blocks made up from DNA parts that can be recombined in different applications. A good example to illustrate this process is engineering a bacterium to become sensitive to environmental pollutants. To fulfill its function, genes have to be integrated to take up, process and react to the pollutant, for example by producing colorful proteins visualizing the contamination.

Most people would agree that the mentioned applications, like pharmaceutical or biofuel production through GMOs, are of major importance now and in the future, and contribute to our prosperity. However, one must ask, which threats does an engineered bacterium pose? In most cases of controlled medical or industrial applications, the risk for environment and human health is very low. Due to high standards and strict physical biocontainment procedures, genetically modified organisms are most certainly not being released. Additionally, spreading of GMOs can be inhibited by means of “kill-switches” to avoid uncontrolled gene transfer with wildtype organisms. In short: modifying microorganisms for industrial purposes is rarely controversially discussed – because of its importance and assessable dangers.

This example shows that one must differentiate between multiple types of genetic engineering to discuss this topic critically. Besides industrial purposes genetic modification gains in importance in medicine as well as agriculture – leading to the main contentious points.

In medical research, genetic modification offers a variety of possibilities: starting with analyzing a disease’s origin up to the development of vaccines and gene therapies. Scientists can research the functionality of metabolic pathways, the cause of diseases, cell structures, genetic deficiencies and so much more. This can for example be achieved by modifying and integrating genes in host organisms or cells to identify their function in a certain process – all with the aim of developing effective therapies and treatments. The Covid-19 pandemic has particularly emphasized the significance of genetic engineering through producing life saving vaccines. Vector vaccines for example are based on a genetically modified, harmless virus, carrying the genetic information for Covid’s spike protein. After invading the body’s cells, the spike protein is synthesized which leads to an immune reaction against the virus. In consequence, our body forms memory cells that target the spike protein with the help of specific antibodies. In case of a following Covid infection, our body is already armed against the invader.

Besides vaccines, genetic modification offers completely new strategies in the fight against cancer. An example, drawn from current research, is the CAR T cell therapy. Applied against leukemia, specific immune cells, T cells, can be collected from the patient’s body and modified to recognize cancer cells. This way, one enables the body to fight against the disease on its own and target tumor cells specifically without the impact of cytotoxic drugs.

As we could see, genetic modification is already present in many medical approaches today. However, critical voices fear the consequences resulting from such severe interventions in human health – with good reason? First of all, before medication or certain therapies are officially approved, many procedures and clinical trials are run to validate its safety. This should secure quality and efficiency in most cases. Therefore, most fears in medical applications are related to direct genetical engineering in humans. Genetic modification allows us to identify genetic disorders in very early stages. However, by now, it is not only possible to diagnose genetic diseases but to treat them by changing a person’s DNA. Genetic therapies could be a huge chance for our society, but also a great risk. What if medical interventions are not only used to cure diseases but also to optimize humans, equipping them with desired abilities? What happens if these lead to the development of a two-class society – “super-humans” versus natural-born people?

At this point, the political instance comes into play, defining ethical standards and regulating the use of genetic intervention. Every member of our society, therefore, has an opportunity to influence these ethical decisions by voting or engaging in political manners. Therefore, one must not only consider the possibilities science offers but most importantly control its implementation.

Besides medical application, synthetic biology is controversially discussed in agricultural usage. By directly modifying plants’ genes, farmers become more and more independent from tedious breeding as well as environmental conditions. Synthetic biology enables us to integrate resistances against parasites, protection against harsh weather conditions or valuable nutrients in crop plants. A common example for the benefits of crop plant modification is the Golden Rice. Golden Rice is enriched with vitamin A, which is achieved by including additional genes for vitamin synthesis. This implementation is especially useful for inhabitants of developmental countries, preventing people from vitamin A dependent deficiencies. Furthermore, plants can also be genetically modified for cultivation under harsh environmental conditions, like high temperatures or poor water supply. In theory, this could contribute to increasing distributive justice in a global perspective. Thus, our planet’s population is constantly growing, year by year. We are running out of resources to supply every member of our society. By genetically modifying crop plants for higher yields, we can initiate countermeasures in the future.

However, genetically engineering plants also has its drawbacks and risks. A common concern mentioned is the intolerance against the modified food itself. According to research done, since the invention of genetically engineered food, its consumption is innocuous. Down to the present day, no connection could be established between consuming modified food and a higher chance of illnesses or allergic reactions. However, except for the impact on our own health conditions, possible effects on our environment are criticized. Growing genetically optimized plants in contact with outdoor nature can have an impact on flora and fauna. First of all, many crop plants are specifically optimized in their resistance against pesticides, which enables farmers to easily banish weeds and parasites from their fields without damaging the crops – at least in theory. Due to horizontal gene transfer, weeds can also adapt to pesticides by exchanging resistance genes with the crop plants. Therefore, even stronger pesticides must be used to inhibit the growth of weeds. This, on the other hand, can pose a danger for the surrounding ecosystems, but also for us humans, if those chemicals spread via the groundwater.

Having said this, the biggest problem of genetically engineered food is still the economic exploitation. Many companies selling modified plant seeds, tailor them for the use of specific pesticides – only sold by the companies themselves. As a result, farmers strongly depend on products from companies in a monopoly position. But there is even more to it than that. To prevent the uncontrolled spreading of genetically modified plants, the seeds can not be used for further breeding. In consequence, new plant seeds have to be bought repeatedly every year. Farmers are driven to be completely dependent on the specialized companies.

At this point, we’ve come full circle again. The invention of genetically optimizing plants for supplying our society itself is brilliant. But when it comes to economic influences and political regulations, further progress has to be made. On the other hand, this is also good news. In democratic states, every single one of us has a voice to be heard. In theory, every single one of us can influence the implementation of synthetic biology to the better. The imagination knows no limits when it comes to future opportunities, genetic engineering offers. Future challenges our society has to face, can be tackled with its help.